IRortb  western 

EVANSTON,  ILL 


Some  Organic  Compounds  of  Mercury 


A  DISSERTATION 


SUBMITTED  IN  PARTIAL  FULFILLMENT  OF  THE  REQUIREMENTS 

OF  NORTHWESTERN  UNIVERSITY  FOR  THE  DEGREE  OF 

DOCTOR  OF  PHILOSOPHY 


DEPARTMENT  OF  CHEMISTRY 


BY 

EDMUND  BURRUS  MIDDLETON 


EASTON,  PA.: 
PRESS  OF  THE  ESCHENBACH  PRINTING  CO. 

1922 


TRortbweetern 

EVANSTON,  Il,L. 


Some  Organic  Compounds  of  Mercury 


A  DISSERTATION 


SUBMITTED  IN  PARTIAL  FULFILLMENT  OF  THE  REQUIREMENTS 

OF  NORTHWESTERN  UNIVERSITY  FOR  THE  DEGREE  OF 

DOCTOR  OF  PHILOSOPHY 


DEPARTMENT  OF  CHEMISTRY 


BY 

EDMUND  BURRUS 


EASTON,  PA.: 

PRESS  OF  THE  ESCHENBACH  PRINTING  CO. 
1922 


SOME  ORGANIC  COMPOUNDS  OF  MERCURY1'2 

Very  few  mercury  derivatives  of  aromatic  esters  are  known.  These 
have  been  prepared  by  direct  mercurization  of  the  esters  by  mercuric  ace- 
tate. Methyl  benzoate  gives  mono-  and  dimercurated  compounds,  the 
structures  of  which  have  not  been  definitely  established.3  0-Chloromer- 
curibenzoic  methyl  ester  has  been  obtained  from  methyl  alcohol  and  sul- 
fidemercuri-benzoyl  chloride.4  The  esters  of  ortho-  and  para-ammo- 
benzoic  acids  and  their  mono-  and  di-alkyl  derivatives  give  mono-  and  di- 
mercurated compounds.5  Esters  of  salicylic  acid  react  with  mercuric 
acetate  giving  mono-mercurated  compounds.6 

Mercurated  acid  chlorides  were  unknown  until  recently,  when  0-chloro- 
mercuri-benzoyl  chloride  was  prepared  from  thionyl  chloride  and  the 

1  Presented  at  the  Rochester  Meeting  of  the  American  Chemical  Society,  April  1921. 

2  This  work  was  done  under  a  grant  from  the  United  States  Interdepartmental 
Social  Hygiene  Board,  Washington,  D.  C.,  Dr.  Valeria  H.  Parker,  Secretary.     Some 
of  the  organic  mercury  compounds  prepared  will  be  tested  for  their  pharmaceutical  value 
by  Dr.  A.  S.  Loevenhart  of  the  University  of  Wisconsin. 

3  Schoeller  and  Schrauth,  Ber.,  53,  636  (1920). 

4  Sachs,  ibdi.,  53,  1741  (1920). 

5  Schoeller  and  Hueter,  ibid.,  47,   1930  (1914).     Schoeller,  Schrauth  and  Liese, 
ibid.,  52  1777  (1919).     Ref.  3,  p.  634. 

6  Ref.  3.  p.  639. 


602603 


lv  V.»^T^«    -.:..:,  •  ,-.-  4 

anhydride  of  0-hydroxymercuri-benzoic  acid.4  Undoubtedly,  it  was 
thought  that  halides  of  phosphorus  could  not  be  used  for  making  acid 
chlorides  containing  mercury,  as  it  has  long  been  known  that  these  halides 
react  with  organomercury  compounds  with  the  elimination  of  the  mercury.7 
During  the  first  part  of  the  present  work  thionyl  chloride  was  used,  but 
it  was  soon  found  possible  to  use  phosphorus  pentachloride  without  re- 
moving the  mercury  from  the  molecule. 

The  present  paper  is  a  report  of  the  preparation  and  properties  of  a 
number  of  esters  and  other  derivatives  of  mercurated  ^-nitrobenzoic 
acid  obtained  from  the  corresponding  mercurated  acid  chloride.  When  the 
mercuric  salt  of  ^-nitrobenzoic  acid  is  heated  to  200°  it  gives  the  inner 
anhydride  of  o-hydroxymercuri-^-nitro-benzoic  acid.8  The  anhydride 
suspended  in  chloroform  reacts  with  phosphorus  pentachloride  to  give 
the  desired  acid  chloride. 


Hg—  O  02N 


It  was  found  difficult  to  obtain  the  acid  chloride  in  a  form  pure  enough 
for  analysis.  The  derivatives  were  prepared  directly  from  the  crude 
product.  The  w-butyl,  w-propyl,  isopropyl,  ethyl  and  methyl  esters  were 
made  from  the  alcohols  and  the  crude  chloride.  The  melting  points  of 
these  compounds  increase  regularly  from  the  w-butyl  ester  to  the  methyl 
ester.  The  acid  chloride  was  also  treated  with  ethylene  chlorohydrine, 
ethylene  bromohydrine,  and  diethylamino-ethyl  alcohol.  Esters  were 
formed  in  each  case,  but  only  the  first  of  these  has  as  yet  been  obtained 
in  pure  form.  The  chloride  reacted  normally  with  aniline  giving  an  ani- 
lide. 

The  action  of  inorganic  iodides  on  the  mercurated  esters  was  studied. 
The  reaction  consists  in  the  change  of  the  compounds  of  the  type,  RHgX, 
to  those  of  the  type,  R2Hg.  The  mercurated  esters  thus  resemble  the 
mercurated  hydrocarbons,  the  mercurated  dimethylanilines,  and  the 
acetylated  mercury  phenols,  rather  than  the  free  mercury  phenols  from 
which  the  mercury  is  entirely  removed  by  the  action  of  inorganic  halides.9 
An  equivalent  amount  of  alkali  is  formed  during  this  removal  of  mercury. 
In  the  case  of  the  mercurated  esters  no  alkali  is  formed.  The  reaction  is 
as  follows 

7  Buckton,  Ann.,  108,  105  (1858).     Cahours,  Ber.,  6,  568  (1875).     Michaelis,  Ann., 
293,  196,  248,  303  (1896). 

8  Blumenthal,  Biochem.  Z.,  32,  60  (1911). 

»  Whitmore,  J.  Am.  Chem.  Soc.   41,  1841  (1919).     Whitmore  and  Middleton,  ibid., 
43,  622  (1921). 


C02R  C02R  C02R 

+  4  KI    =  ,/\  --  Hg  --  /\         +  K2HgI4  +  2  KC1. 


NO2  NO2  NO2 

These  derivatives  of  mercury  diphenyl  are  less  soluble  than  the  corre- 
sponding chlorides  and  their  melting  points  are  higher.  They  react  in 
the  usual  way  with  mercuric  chloride  forming  the  compounds  of  the  type, 
RHgCl.  They  can  be  saponified  without  breaking  the  C-Hg  linkage. 
The  acid  obtained  by  this  process  is  0-mercuri-fos(£-nitrobenzoic  acid), 
which  has  been  prepared  by  a  regulated  alkaline  reduction  of  o-hydroxy- 
mercuri-p-nitrobenzoic  acid.8 

The  acid  chloride  prepared  by  Sachs  was  also  prepared  by  means  of 
phosphorus  pentachloride.  The  w-butyl  ester  prepared  from  it  was 
identical  with  that  prepared  from  a  sample  of  the  acid  chloride  made  with 
thionyl  chloride. 

Experimental 

The  mercuric  salt  of  ^-nitrobenzoic  acid  was  prepared  from  the  sodium 
salt  by  precipitation  with  a  nearly  neutral  solution  of  the  calculated 
amount  of  mercuric  nitrate.  The  precipitate  was  washed  thoroughly 
and  dried.  Fifty  g.  of  the  mercuric  salt  was  heated  for  3  hours  at  200-220° 
in  a  small  flask  immersed  in  an  oil-bath.  When  samples  of  more  than  100 
g.  were  heated,  explosions  sometimes  occurred.  After  heating  the  mix- 
ture, it  was  cooled  and  the  ^-nitrobenzoic  acid  which  formed  was  removed 
by  repeated  extractions  with  small  amounts  of  ether.  The  residue  in- 
soluble in  ether  consisted  of  the  nearly  pure  anhydride  of  0-hydroxymer- 

curi-^-nitrobenzoic  acid. 

C02C4H9 

w-Butyl  Ester  of  0-Chloromercuri-£-nitrobenzoic  acid,  '    .  —  Ten  g.  of 

NO2 

the  anhydride  was  suspended  in  100  cc.  of  chloroform  and  treated  in  the  cold  with  7  g. 
of  phosphorus  pentachloride.  Vigorous  action  ensued.  The  mixture  was  then  heated 
under  a  reflux  condenser  about  30  minutes.  The  solution  was  then  cooled  and  filtered. 
The  precipitate  was  washed  with  chloroform  to  remove  phosphorus  oxychloride  and  al- 
lowed to  dry.  The  dry  acid  chloride  was  then  treated  with  10  cc.  of  n-  butyl  alcohol  and 
heated  until  it  completely  dissolved  As  this  product  cooled,  white  crystals  of  the  n- 
butyl  ester  separated.  These  are  fairly  soluble  in  ethyl  alcohol,  benzene,  chloroform, 
acetone,  ether,  and  carbon  tetrachloride.  The  product  was  recrystallized  from  hot 
ethyl  alcohol  until  it  showed  a  constant  melting  point  of  125-126°  (uncorr.).  Nine  g. 
of  the  ester  was  obtained  from  10  g.  of  the  crude  anhydride;  yield,  70%.  Most  of  the 
loss  occurs  in  the  conversion  of  the  acid  to  the  acid  chloride  which  is  never  complete. 
Analyses.  Subs.,  0.1754:  Hg,  0.0770.  Subs.,  0.1991,  0.2033:  CO2,  0.2071, 
0.2146.  Calc.  for  CnH12O4NClHg:  C,  28.8;  Hg,  43.8.  Found:  C,  28.4,  28.8;  Hg, 
43.9.10 


10  The  analyses  for  mercury  were  carried  out  by  the  "gold  crucible  method"  de- 


w-Propyl  Ester. — The  procedure  given  above  was  employed,  except  that  10  cc. 
of  w-propyl  alcohol  was  used  instead  of  butyl  alcohol.  The  product,  after  repeated 
crystallizations  from  ethyl  alcohol,  melted  at  145-150  °.  No  sharper  melting  point  could 
be  obtained.  The  ester  is  moderately  soluble  in  ethyl  alcohol,  chloroform,  ether, 
carbon  tetrachloride,  acetone  and  benzene. 

Analyses.  Subs.,  0.1943,  0.1911:  Hg,  0.0887,  0.0871.  Calc.  for  CIOH10O4NClHg: 
Hg,  45.2.  Found:  45.6,  45.6. 

/sopropyl  Ester. — The  same  procedure  was  used  as  with  the  other  esters.  The 
purified  product  melted  at  179-180°. 

Analyses.  Subs.,  0.1981,  0.2089:  Hg,  0.0897,  0.0943.  Calc.  for  Ci0Hi0O4NClHg: 
Hg,  45.2.  Found:  45.3,  45.1. 

Ethyl  Ester. — The  purified  product  melted  at  220-222°.  Its  properties  and  solu- 
bilities are  similar  to  those  of  the  other  esters. 

Analyses.  Subs.,  0.1945,  0.1800:  Hg,  0.0899,  0.0842.  Calc.  for  C9H8O4NClHg: 
Hg,  46.6.  Found:  46.2,  46.8. 

Methyl  Ester. — The  product,  purified  by  crystallization  from  methyl  alcohol, 
melted  at  240-245°. 

Analyses.  Subs.,  0.2206,  0.2008:  Hg,  0.1077,  0.0976.  Calc.  for  CsHeC^NClHg: 
Hg,  48.2.  Found:  48.9,  48.6. 

Chloro-ethyl  Ester. — This  ester  was  prepared  from  the  crude  acid  chloride  and 
ethylene  chlorohydrine  in  the  usual  way.  Its  solubilities  and  properties  resembled 
those  of  the  other  esters.  Crystallization  from  ethyl  alcohol  gave  a  product  melting 
at  163-164°. 

Analyses.  Subs.,  0.2010,  0.2023,  0.2323:  Hg,  0.0865,  0.0879,0.1000.  Calc.  for 
C9H705NCl2Hg:  Hg,  43.2.  Found:  43.0,  43.4,  43.1. 

Attempts  at  Preparation  of  the  Bromo-ethyl  and  Alkamine  Esters 
The  acid  chloride  was  found  to  react  readily  with  ethylene  bromohydrine  and  with 
diethylammo-ethyl  alcohol,  but  no     homogeneous  product  was  obtained  from  either 
reaction.     Further  attempts  are  being  made  to  prepare  these  esters  in  a  state  of  purity. 

Determination  of  the  Position  of  the  Mercury  in  the  Esters 

When  the  mercurated  esters  reacted  in  the  cold  with  bromine  water,  they  gave 
products  which,  after  saponification  and  acidification,  were  converted  into  o-bromo-p- 
nitrobenzoic  acid;  this  was  identified  by  its  melting  point  (163°)  and  by  analyses  for 
bromine. 

Anilide  of  0-Chloromercuri-/>-mtrobenzoic  Acid. — Ten  g.  of  the  crude  acid  chloride 
was  heated  with  6  cc.  of  aniline  until  solution  took  place.  The  anilide  separated  as  the 
mixture  cooled.  It  was  washed  free  from  aniline  with  benzene  and  recrystallized  from 
ethyl  alcohol.  The  product  was  soluble  in  hot  ethyl  alcohol,  slightly  soluble  in  ether 
and  insoluble  in  most  other  organic  solvents. 

Analyses.  Subs.,  0.2112,  0.2001:  Hg,  0.0878,  0.0832.  Calc.  for  C13H9O3N2-ClHg: 
Hg,  42.0.  Found:  41.6,  41.6. 

CO2Bu  CO2Bu 

w-Butyl  Ester  of  0-Mercuri-&«(£-nitrobenzoic  Acid),   f 

NO2  NO2 

scribed  on  p.  365  of  "Organic  Compounds  of  Mercury"  (Chemical  Catalog  Co.,  N.  Y.  C. 
1921)  by  one  of  us  (W.).  In  the  analysis  of  organic  mercury  compounds  containing 
nitro  groups  the  heating  must  be  carried  out  very  cautiously  to  avoid  slight  explosions 
which  are  likely  to  blow  foreign  material  against  the  amalgam. 


Eight  g.  of  the  w-butyl  ester  of  o-chloromercuri-/>-nitro-benzoic  acid  in  100  cc.  of  ethyl 
alcohol  was  refluxed  with  5  g.  of  potassium  iodide  for  1  hour.  As  the  reaction  mixture 
cooled,  the  mercuri-fo's  compound  separated  in  colorless  crystals.  The  mother  liquor 
contained  large  amounts  of  inorganic  mercury.  The  product  was  recrystallized  from 
ethyl  alcohol;  m.  p.,  158°;  yield,  5  g.  or  95%.  Its  solubilities  resembled  those  of  the 
corresponding  chloromercuri  compound  but  were  slightly  less. 

Analyses.  Subs.,  0.2521,  0.1461:  Hg,  0.0791,  0.0459.  Subs.,  0.1781,  0.2214: 
CO2,  0.2585,  0.3240.  Calc.  for  C22H24O8N2Hg:  C,  40.9;  Hg,  31.1.  Found:  C,  39.6,  39.9; 
Hg,  31.4,  31.4. 

One  g.  of  this  compound  was  heated  with  0.43  g.  of  mercuric  chloride  (one  mol)  in 
50  cc.  of  ethyl  alcohol  for  30  minutes.  The  corresponding  chloromercuri  compound, 
1.2  g.  separated  as  the  product  cooled;  m.  p.,  125°.  The  chloride  was  analyzed. 

Analysis.  Subs.,  0.1923:  Hg,  0.0839.  Calc.  for  CnH12O4NClHg:  Hg,  43.8. 
Found:  43.7. 

Five  g.  of  the  ester  of  the  mercuries  compound  suspended  in  100  cc.  of  ethyl 
alcohol  was  heated  with  5  g.  of  sodium  hydroxide.  When  all  of  the  solid  had  dissolved, 
the  solution  was  cooled.  The  sodium  salt  which  separated  was  collected,  dissolved  in 
water,  and  the  solution  acidified.  The  amorphous  precipitate  was  o-mercuri-bis(p- 
nitrobenzoic  acid),8  as  was  shown  by  analyses  for  mercury. 

w-Propyl  Ester. — Seven  g.  of  the  corresponding  chloromercuri  ester  was  heated 
under  a  reflux  condenser  with  5  g.  of  potassium  iodide  in  100  cc.  of  alcohol  for  1  hour. 
Colorless  crystals  of  the  mercuri-bis  compound  separated  as  the  solution  cooled.  After 
recrystallization  from  ethyl  alcohol,  it  melted  at  189°;  yield  4.6  g.,  or  92%. 

Analyses.  Subs.,  0.1638,  0.1705:  Hg,  0.0538,  0.0549.  Calc.  for  C2oH2oO8N2Hg: 
Hg,  32.5.  Found:  32.8,  32.2. 

Treatment  of  this  compound  with  mercuric  chloride  in  alcohol  gave  the  w-propyl 
ester  of  o-chloromercuri-/>-nitrobenzoic  acid  melting  at  145-150°. 

Ethyl  Ester. — This  ester  was  prepared  in  the  same  way  as  were  the  w-butyl  and 
w-propyl  esters  and  resembled  them  in  properties;  m.  p.,  227-232°. 

Analyses.  Subs.,  0.1909,  0.1877:  Hg,  0.0650,  0.0644.  Calc.  for  C18H16O8N2Hg : 
Hg,  34.1.  Found:  34.1,34.3. 

n-Butyl  Ester  of  o-Chloromercuri-benzoic  Acid. — Seven  g.  of  the  anhydride  of 
o-hydroxymercuri-benzoic  acid  was  treated  with  5  g.  of  phosphorus  pentachloride  in 
50  cc.  of  chloroform.  Vigorous  action  took  place.  As  soon  as  this  had  ceased,  the  mix- 
ture was  cooled  and  the  acid  chloride  was  collected  on  a  filter.  It  was  washed  with 
chloroform  and  allowed  to  dry.  The  product  was  heated  with  10  g.  of  w-butyl  alcohol 
until  all  of  it  dissolved.  After  several  recrystallizations  from  alcohol  it  melted  at  115°. 

Two  g.  of  the  0-chloromercuri-benzoyl  chloride  prepared  by  the  thionyl  chloride 
method4  was  treated  with  w-butyl  alcohol  in  the  same  way.  The  purified  product  melted 
at  116°.  The  melting  point  of  the  mixture  of  the  two  products  was  not  lower. 

Analysis.  Subs.,  0.1668:  Hg,  0.0813.  Calc.  for  CnH13O2ClHg:  Hg,  48.4.  Found: 
48.7. 

Summary 

1.  Phosphorus  pentachloride  can  be  used  as  well  as  thionyl  chloride 
for  making  acid  chlorides  of  mercurated  aromatic  acids. 

2.  The  acid  chloride  of  o-chloromercuri-p-nitrobenzoic  acid  was  used 
to  prepare  the  following  esters  of  the  acid:    methyl,  ethyl,  w-propyl,  iso- 
propyl  and  w-butyl. 


8 

3.  These  compounds  react  with  inorganic  iodides  to  form  the  corre- 
sponding compounds  of  the  type,  R2Hg. 

4.  These  compounds  can  be  saponified  without  breaking  the  C-Hg 
linkage. 

This  work  was  carried  out  under  the  direction  of  Professor  Frank  C. 
Whitmore.     The  author  desires  to  thank  him  for  his  advice  and  criticism. 


(Reprinted  from  the  Journal  of  the  American  Chemical  Society, 
Vol.  XLIII.     No.     3.        March.  1921.) 

[CONTRIBUTION  FROM  THB  CHEMICAL  LABORATORY  OF  NORTHWESTERN  UNIVERSITY.] 

REACTION  OF  ALKALI  HALIDES  WITH  MERCURY  DERIVATIVES 

OF  PHENOL.1 

BY  F.  C.  WHITMORE  AND  EDMUND  BURRUS  MIDDLETON. 

Received  November  22,  1920. 

Mercury  derivatives  of  phenol  lose  their  mercury  quantitatively  when 
treated  with  a  solution  of  potassium  iodide.  Ordinarily,  an  aromatic 
mercury  compound  does  not  react  with  iodides  to  give  mercuric  iodide. 
Under  some  conditions,  one  half  of  the  mercury  is  removed  as  the  iodide 
and  the  other  half  remains  combined  in  a  derivative  of  mercury  diphenyl, 
2R-Hg-I  +  2KI  =  K2HgI4  -f-  R2Hg.  In  a  study  of  the  mercury  deriv- 
atives of  ^-bromo-dimethylaniline,2  it  was  found  that  the  reaction  of 
potassium  iodide  with  5-bromo-2-dimethylamino-phenylmercuric  acetate 
gave  a  considerable  amount  of  ^-bromo-dimethylaniline  as  well  as  the 
expected  mercury  diphenyl  derivative.  The  formation  of  metallic  mer- 
cury during  the  reaction  made  it  appear  that  the  alcohol  or  some  other 
substance  was  acting  as  a  reducing  agent.  However,  this  could  not 
explain  the  formation  of  all  of  the  bromo-dimethylaniline,  since  the 
amount  of  this  substance  produced  was  greater  than  the  free  mercury 
would  require.  A  search  through  the  literature  revealed  a  number  of 
cases  in  which  mercury  attached  to  carbon  is  replaced  by  hydrogen  under 
the  influence  of  iodide  solutions.  While  this  reaction  is  universal 
for  Hg-N  compounds,  it  is  unusual  for  Hg-C  compounds.  Since  there 
is  undoubtedly  some  relation  between  the  therapeutic  value  of  mercury 
carbon  compounds  and  the  stability  of  the  Hg-C  linkage,  it  seemed 
desirable  to  study  the  conditions  under  which  this  linkage  between  mer- 
cury and  carbon  is  broken  by  inorganic  halides. 

Biilmann  found  that  mercury  derivatives  of  malonic  acid  and  of  its 
esters3  when  treated  with  potassium  iodide  solution  yield  mercuric  iodide 
and  one  molecule  of  potassium  hydroxide  for  every  Hg-C  linkage.  With 
potassium  iodide  mercury  is  removed  in  a  different  way  from  the  products 
of  the  action  of  mercuric  salts  upon  various  unsaturated  acids.4  In  this 
case  the  original  unsaturated  acid  is  recovered.  The  difference  in  the  2 
reactions  may  be  shown  by  the  equations 

R-Hg-I  +  SKI  +  H2O  =  RH  +  K2HgI4  +  KOH 
R-CHOH-CHHgI-CO2K  +  3KI  =  R-CH  =  CH-CO2K  +  K2HgI4  +  KOH. 

1  Part  of  this  work  was  done  under  a  grant  from  the  U.  S.  Interdepartmental 
Social  Hygiene  Board,  Dr.  T.  A.  Storey,  Secretary.     Presented  before  the  Organic 
Division  of  the  American  Chemical  Society  at  the  Chicago  Meeting,  September  1920. 

2  THIS  JOURNAL,  41,  1851  (1919). 

»  Biilmann,  Ber.,  35,  2581  (1902);  42,  1070  (1909). 

4  Biilmann,  ibid.,  35,  2571  (1902);  43,  568  (1910);  also  compare  Manchot,  Ann., 
420,  183  (1920). 


620  $.   C.    WHITMORE   AND   EDMUND   BURRUS  MIDDLETON. 

In  the  second  case  the  replacement  of  the  mercury  by  hydrogen  is  ac- 
companied by,  or  followed  by,  the  loss  of  water.  The  mercury  derivative 
of  cyano-acetic  acid1  behaves  in  a  manner  similar  to  that  of  the  mercury 
malonic  derivatives.  The  mercury  derivative  of  camphor2  is  said  to  be 
"decomposed"  rapidly  by  an  acetone  solution  of  potassium  iodide. 

In  the  aromatic  series  a  few  cases  of  this  replacement  are  recorded. 
Dimroth  found  that  ^-aminophenylmercuric  acetate,3  when  treated  with 
potassium  iodide  gave  a  small  amount  of  inorganic  mercury.  This  may 
be  due  to  the  formation  of  mercuric  iodide  during  the  formation  of  the 
mercury  diphenyl  derivative,  or  during  a  splitting  of  the  Hg-C  linkage, 
accompanied  by  the  formation  of  aniline  and  alkali.  Pesci  found  that 
salts  of  0-(chloromercuri)benzoic  acid4  when  treated  with  sodium  halides 
give  sodium  benzoate,  mercuric  halide,  and  sodium  hydroxide. 

2-5-Cresylmercuric  acetate5  is  said  to  be  "decomposed"  by  potassium 
iodide.  Brieger  and  Schulemann  in  their  exhaustive  study  of  the  mer- 
curation  of  the  various  naphthalene  intermediates6  of  the  coal  tar  dye 
industry  found  that  the  mercurated  naphthols  are  very  sensitive  to  alkali 
halides.  In  some  cases  they  titrated  the  alkali  formed  and  drew  conclu- 
sions as  to  the  completeness  of  the  splitting  of  the  Hg-C  linkage.  They 
found  that  potassium  iodide  gives  a  quantitative  replacement,  while  the 
bromide  and  chloride  give  it  to  a  decreasing  extent.  In  other  cases  they 
did  not  determine  the  alkali  formed,  but  studied  the  "loosening"  effect 
of  the  halide  by  treating  with  sulfides.  In  many  instances,  the  pure  mer- 
cury compound  gave  no  action  with  ammonium  sulfide,  but,  when  treated 
with  potassium  iodide  and  then  with  the  sulfide,  gave  mercuric  sulfide. 
The  bromide  and  chloride  of  potassium  had  a  similar  but  weaker  effect. 
Brieger  and  Schulemann  found  that  the  mercurated  naphthylamines  were 
split  much  less  readily  than  the  corresponding  naphthols. 

In  view  of  the  many  cases  of  this  peculiar  replacement  of  organic  mer- 
cury, and  the  lack  of  details,  it  seemed  desirable  to  study  the  reaction 
with  some  substances  simpler  than  the  complicated  intermediates  used 
by  Brieger  and  Schulemann.  The  mercurated  phenols7  prepared  by  Dim- 
roth  offered  an  ideal  subject  for  the  study. 

Dimroth's  method  of  treating  a  solution  of  phenol  with  mercuric  acetate 
solution  was  discarded  because  of  the  large  amount  of  dimercurated 
product  formed.  It  was  found  that  phenol,  without  a  solvent,  heated 

1  Petterson,  /.  prakt.  Chem.  [2]  86,  458  (1912). 
*  Marsh  and  Fleming-Struthers,  /.  Chem.  Soc.,  95,  1777  (1909). 
3  Z.  anorg.  Chem.,  33,  314  (1903). 

«  Pesci,  Gazz.  chim.  ital.,  32,  II,  277  (1902);  Centralbl,  1902,  II,  1454. 
6  Dimroth,  Ber.,  35,  2853  (1902).     Compare  Brieger  and  Schulemann,  J.  prakt. 
Chem.,  [2]  89,  104  (1914). 

6  Ibid .,  97  ff. 

7  Habilitationsschr.,  Tubingen,  1900;  Centralbl.,  1901,  I,  452;  Ber.,  35,  2855  (1902). 


MERCURY  DERIVATIVES  OP  PHENOL.  621 

with  mercuric  acetate  on  the  steam-bath  gives  a  mixture  of  the  ortho  and 
para  compounds  free  from  the  disubstituted  product.  These  were  sep- 
arated by  Dimroth's  method  of  forming  the  chlorides;  the  ^-hydroxy- 
phenylmercuric  chloride  is  insoluble  in  hot  water,  while  the  ortho  com- 
pound is  soluble.  At  temperatures  above  that  of  the  steam-bath,  the 
total  yield  was  decreased  somewhat,  but  the  amount  of  ortho  compound 
increased  slightly. 

The  3  mercurated  phenols  were  boiled  with  aqueous  potassium 
iodide.  In  each  case  the  solid  soon  dissolved  and  the  solution  became 
alkaline.  After  boiling  for  30  minutes  the  alkali  was  titrated  with  stand- 
ard acid  and  phenolphthalein.  The  ortho  and  para  compounds  gave 
almost  one  molecule  of  alkali  while  the  di-  compound  gave  almost  2. 

HO-C6H4-HgCl  +  KI  +  H20  =  HO-C6H5  +  K2HgI4  +  KOH  +  KC1. 
The  dimercuric  chloride  compound  would  give  2  molecules  of  potassium 
hydroxide.    When  potassium  bromide  was  used  in  place  of  the  iodide, 
only  a  small  amount  of  alkali  was  formed.     Potassium  chloride  gave  no 
alkali  even  on  prolonged  boiling. 

It  seemed  desirable  to  find  out  whether  this  unusual  removal  of  mer- 
cury from  the  aromatic  nucleus  depended  on  the  presence  of  the  phenolic 
hydroxyl.  To  answer  this  question  the  acetyl  derivatives  of  the  o-  and  p- 
hydroxyphenylmercuric  chlorides  were  prepared  and  treated  with  potas- 
sium iodide.  There  was  no  splitting  of  the  Hg-C  linkage  in  these  cases. 
The  solutions  remained  neutral.  If  splitting  had  occurred  the  alkali 
formed  would  probably  have  saponified  the  phenyl  acetate  to  form  sodium 
acetate  and  free  phenol.  No  phenol  was  obtained  as  was  shown  by  dis- 
tillation of  the  neutral  mixture  with  steam  and  a  test  of  the  distillate 
with  ferric  chloride.  The  acetylated  0-hydroxyphenylmercuric  chloride 
reacted  with  aqueous  potassium  iodide  to  form  the  organomercuric  iodide. 
The  hot  mother  liquor  from  this  iodide  gave  a  small  amount  of  the  cor- 
responding mercury  diphenyl  derivative,  o,o/-mercuri-bis(phenyl  acetate). 
The  same  reaction,  carried  out  in  alcohol  solution,  gave  only  the  iodide. 
The  acetylated  ^-hydroxyphenylmercuric  chloride  gave  only  the  corres- 
ponding iodide. 

As  the  yield  of  the  substituted  mercury  diphenyl  is  often  larger  with 
sodium  thiosulfate  than  with  potassium  iodide,  the  former  reaction  was 
tried  with  the  acetylated  mercury  phenols.  In  each  case,  a  fair  yield  of 
the  mercury  diphenyl  derivative  was  obtained.  The  proof  of  the  struc- 
ture of  these  compounds  lies  in  the  fact  that  they  react  quantitatively 
with  mercuric  chloride  to  give  the  original  acetylated  hydroxyphenyl- 
mercuric  chlorides. 
2CH3CO-OC6H4-HgCl  +  2Na2S2O3  =  (CHsCO-OCeH^Hg  + 

Na2Hg(S2O3)2  +  2NaCl. 
(CH3CO-OC6H4)2Hg  +  HgCl2  =  2CH3CO-OC6H4-HgCl. 


622  F.    C.    WHITMORE   AND   EDMUND   BURRUS   MIDDLETON. 

Dirnroth  was  able  to  change  the  0-hydroxyphenylmercuric  chloride  to 
the  corresponding  mercury  diphenyl  derivative  but  did  not  carry  out 
the  reaction  with  the  para  compound.  Dimroth's  work  was  repeated 
and  confirmed.  It  seemed  possible  that  the  missing  para  mercury  di- 
phenyl derivative  might  be  made  by  saponifying  the  corresponding 
acetylated  substance.  When  this  was  tried  the  product  was  found  to  be 
a  monophenylmercuric  derivative.  In  other  words,  one  of  the  phenyl 
groups  had  been  removed  from  the  mercury  by  the  action  of  hot  sodium 
hydroxide.  Apparently  this  is  a  new  method  of  splitting  a  Hg-C  linkage. 
It  is  another  example  of  the  "loosening"  effect  of  hydroxyl  or,  in  this  case 
of  the  ONa  group,  on  a  mercury  atom  attached  to  the  same  nucleus. 
The  reactions  involved  may  be  written  thus : 

(CH3CO-OC6H4-)3Hg+4NaOH  =  (NaO-C6H4-)2Hg+2CH3CO2Na+2H2O 
2(NaO-C6H4-GHg-j-H2O  =  NaO-C6H4-HgOH+C6H5ONa 
Neutralization  with  dil.  acetic  acid  precipitated  (HO-C6H4-Hg)2O  in- 
stead of  the  corresponding  hydroxide.1  An  analogous  reaction  occurs 
and  a  similar  product  is  obtained  with  the  acetylated  ortho  diphenyl 
derivative.  Both  the  complex  organomercuric  oxides  were  converted  to 
the  original  chlorides  by  treatment  with  acetic  acid  and  sodium  chloride. 
The  same  conversion  was  brought  about  by  treatment  with  ethyl  acetate 
and  then  with  sodium  chloride  solution.2  All  the  organic  mercury  com- 
pounds studied  reacted  with  ammonium  sulfide  only  on  standing.  They 
reacted  slowly  with  cold  cone,  hydrochloric  acid,  but  rapidly  with  the 
hot  acid  to  give  inorganic  mercury  salts  which  formed  an  immediate  pre- 
cipitate with  hydrogen  sulfide. 

Experimental. 

Preparation  of  the  0-  and  ^-Hydroxyphenylmercuric  Chlorides. — Twelve  g.  of 
phenol  (about  1.5  molecules)  was  heated  on  the  steam-bath  and  25  g.  of  mercuric  acetate 
was  added  gradually  while  the  mixture  was  stirred  constantly.  When  all  the  acetate 
had  dissolved,  boiling  water  was  added  and  the  mixture  was  boiled  for  a  few  minutes. 
Then  a  hot  solution  of  5  g.  of  sodium  chloride  was  added.  The  />-hydroxyphenyl- 
mercuric  chloride  precipitated  at  once.  The  mixture  was  filtered  while  hot.  The 
solution,  on  standing,  deposited  crystals  of  the  ortho  compound.  The  properties  of 
these  substances  agreed  with  those  recorded  by  Dimroth.  When  the  preparation 
was  carried  out  as  described,  no  dimercury  compound  was  formed.  This  was  proved 
by  the  complete  solubility  of  the  mixture  in  boiling  water.  The  amounts  of  ortho  and 
para  compounds  formed  varied  only  slightly  with  the  temperature  of  reaction.  With  25-g. 
portions  of  mercuric  acetate  (about  85%  pure),  the  following  amounts  of  para  and 
ortho  compounds  were  obtained,  at  100°,  18  g.  of  para  and  7  g.  of  ortho;  at  125°,  16  g. 
of  para  and  8  g.  of  ortho;  at  150°,  14  g.  of  para  and  8  g.  of  ortho. 

Preparation  and  Properties  of  the  Acetyl  Derivatives  of  the  Hydroxyphenyl- 
mercuric  Chlorides. — Fourteen  g.  of  the  o-hydroxyphenylmercuric  chloride  was  treated 
with  a  slight  excess  of  acetyl  chloride  (3  cc.)  and  warmed  gently.  After  the  evolution 

1  Compare  Dimroth,  Ber.,  35,  2854  (1902). 

2  Compare  THIS  JOURNAL,  41,  1854,  Summary,  3  (1921). 


MERCURY  DERIVATIVES  OF  PHENOL.  623 

of  hydrochloric  acid  had  ceased,  the  substance  was  pressed  on  a  porous  plate  and  then 
washed  many  times  with  water.  Twelve  g.  of  the  acetyl  derivative  was  obtained 
(about  an  80%  yield).  The  para  compound  was  prepared  in  a  similar  way.  Melting 
points  (uncorr.):  ortho,  170-1°;  para,  235°. 

Analyses.— Calc.  for  C8H7OClHg:  Hg,  54.05.  Found:  ortho,  54.1,  54.0,  54.0; 
para,  53.8,  53.5. 

Reaction  of  Potassium  Iodide  with  the  Mercurated  Phenols. — When  the  o-hydroxy- 
phenyl  mercuric  chloride,  the  corresponding  para  compound,  and  the  o,£-diacet- 
oxymercoriphenol  were  boiled  with  excess  of  potassium  iodide  solution  they  dissolved, 
the  solmtions  became  alkaline,  and  phenol  and  inorganic  mercury  compounds  were 
formed.  The  alkali  was  titrated  with  standard  acid.  The  procedure  was  as  follows. 
1  g.  of  the  mercury  compound  was  boiled  for  half  an  hour  with  50  cc.  of  water  and  2  g. 
of  potassium  iodide.  Water  was  added  to  replace  that  lost  by  evaporation.  The  base 
was  then  titrated  with  0.1  N  sulfuric  acid.  One  g.  of  the  0-hydroxyphenylmercuric 
chloride  gave  30.12  cc.  of  0.1  N  potassium  hydroxide,  while  that  calculated  was 
31.90.  One  g.  of  the  para  compound  gave  29.12  cc.  of  0.1  N  potassium  hydroxide, 
as  compared  with  calculated  31.90  cc.  One  g.  of  the  dimercury  acetate  compound 
gave  32.50  cc.  of  0.1  N  hydroxide,  compared  with  32.6  cc.  calculated  for  2  molecules. 

An  experiment  was  tried  with  the  ortho  compound  in  which  potassium  bromide 
or  chloride  was  used  instead  of  the  iodide.  The  compound  boiled  with  the  chloride 
gave  no  alkali.  Long  boiling  of  it  with  the  bromide  gave  only  a  slight  alkalinity. 
Similar  results  were  obtained  with  the  para  and  with  the  di-compounds. 

Reaction  of  Potassium  Iodide  with  the  Acetylated  Compounds. — When  the  acetyl 
derivative  of  the  o-  or  ^-hydroxyphenylmercuric  chlorides  was  boiled  with  potassium 
iodide  solution,  no  alkali  ©r  phenol  was  formed.  Thus,  1.5  g.  of  the  ortho  acetylated 
compound  was  boiled  for  one  hour  with  50  cc.  of  water  and  2  g.  of  potassium  iodide. 
The  solution  was  still  neutral.  The  solution  was  distilled  with  steam  and  the  distillate 
was  tested  with  ferric  chloride.  No  color  resulted.  When  the  aqueous  nitrate  from 
the  organomercuric  iodide  was  cooled,  it  yielded  0.2  g.  of  white  needle  shaped  crystals 
melting  at  125°*  This  substance  was  proved  to  be  the  mercury  diphenyl  derivative, 
mercury  di-(o  hydroxyphenyl  acetate),  (CH3CO-OC6H4-)2Hg.  The  yield  was  only  about 
20%.  The  £ara-acetylated  compound  is  changed  to  the  organomercuric  iodide  only 
after  long  boiling  with  potassium  iodide. 

Reaction  of  Sodium  Thiosulfate  with  the  Acetylated  Compounds. — Seven  g.  of  the 
ortho  acetyl  derivative  was  dissolved  in  a  thiosulfate  solution  containing  15  g.  of  the 
crystalline  salt  in  100  cc.  of  water.  The  mercury  compound  dissolved  fairly  readily  to 
give  a  clear  solution.  As  this  solution  stood,  crystals  of  the  mercury  diphenyl  compound 
separated.  After  3  days,  3.6  g.  of  the  o,  o'-mercuribisphenol  diacetate  had  separated 
as  white  needles,  m.  p.  125  °.  Yield,  about  80%.  They  are  slightly  soluble,  on  heating, 
in  alcohol,  in  benzene,  and  in  chloroform;  very  slightly  soluble  in  ether. 

Analyses.— Calc.  for  Ci6H14O4Hg:  Hg,  42.62.     Found:  42.7,  42.0. 

Similarly,  the  para  acetylated  compound  was  treated  with  thiosulfate.  The 
para  diphenyl  derivative  separated  from  the  thiosulfate  solution  as  white  crystals, 
m.  p.  172-3°,  much  more  slowly  than  did  the  ortho  compound.  The  yield  was  poorer; 
10  g.  of  the  chloride  gave  only  3  g.  of  the  diphenyl  compound,  about  a  50%  yield. 

Analyses. — Calc.  for  Ci6Hi4O4Hg:  Hg,  42.62.     Found:  42.4,  42.3. 

Reaction  of  Mercuric  Chloride  with  the  Acetylated  Diphenyl  Derivatives. — The 
structure  of  the  diphenyl  derivatives  was  proved  by  splitting  them  with  mercuric 
chloride  to  form  the  original  chlorides.  One  g.  of  the  ortho  diphenyl  derivative  was 
boiled  with  50  cc.  of  water  containing  0.5  g.  of  mercuric  chloride  and  yielded  1.4  g.  of 
the  ortho  CH3CO-OC6H4-HgCl,  m.  p.  170°.  Similarly,  the  para  diphenyl  compound, 
gave  the  original  chloride  (m.  p.  235°),  quantitatively. 


624  F.    C.    WHITMORE   AND   EDMUND   BURRUS   MIDDLETON. 

Reaction  of  the  Acetylated  Mercury  Compounds  with  Sodium  Hydroxide. — Three 
g.  of  [the  ortho  acetylated  mercury  diphenyl  compound  was  boiled  for  20  minutes 
with  50  cc.  of  5%  sodium  hydroxide.  The  solution  was  cooled  and  made  exactly 
neutral  with  dil.  acetic  acid.  One  and  seven-tenths  g.  of  a  white  amorphous  substance 
separated.  It  did  not  melt,  but  darkened  at  a  high  temperature.  Analyses  indicated 
that  it  was  the  oxide  obtained  by  Dimroth,  di(hydroxyphenylmer curie)  oxide. 

Analyses.— Calc.  for  C12H10O3Hg2:  Hg,  66.5.     Found:  Hg,  67.0,  66.7,  66.2. 

When  treated  with  dil.  acetic  acid  and  sodium  chloride  it  gave  the  original  chloride, 
hydroxyphenylmercuric  chloride.  When  the  oxide  was  boiled  with  ethyl  acetate  it 
dissolved  readily.  When  this  solution  was  boiled  with  sodium  chloride  solution  the 
original  chloride  was  formed. 

The  acetylated  para  mercury  diphenyl  compound  was  split  in  the  same  way  by 
boiling  with  dilute  sodium  hydroxide.  A  similar  complex  oxide  was  formed.  Like 
its  isomer  it  was  amorphous  and  did  not  melt. 

Analyses.— Calc.  for  C12H10O3Hg2:  Hg,  66.5.     Found:  Hg,  66.8,  67.0. 

This  complex  oxide  was  changed  to  the  ^-hydroxyphenylmercuric  chloride  by 
treatment  with  dilute  acetic  acid  and  sodium  chloride,  and,  also,  by  treatment  with 
ethyl  acetate  and  sodium  chloride. 

Reaction  of  the  Acetylated  Compounds  with  Sulfides  and  with  Acids. — The  ortho 
and  para  acetylated  hydroxyphenylmercuric  chlorides  suspended  in  water  and  treated 
with  hydrogen  sulfide  for  15  minutes  gave  no  mercuric  sulfide.  After  contact  with 
ammonium  sulfide  for  about  half  an  hour,  they  commenced  to  blacken.  The  free  mer- 
cury phenols  acted  a  little  more  rapidly.  The  acetylated  mercury  diphenyl  com- 
pounds gave  no  action  with  ammonium  sulfide  in  less  than  3  days;  then  a  red  precipitate 
began  to  form. 

The  acetylated  hydroxyphenylmercuric  chlorides  treated  with  cone,  hydrochloric 
acid  and  hydrogen  sulfide  showed  no  reaction.  After  standing  for  half  an  hour,  or 
if  they  were  heated,  mercuric  sulfide  was  formed.  The  acetylated  mercury  diphenyl 
compounds  treated  with  cone,  hydrochloric  acid  and  hydrogen  sulfide  gave  no  mer- 
curic sulfide,  until  the  mixture  had  stood  for  about  an  hour  or  had  been  heated. 

Summary. 

1.  Mercuric  acetate  reacts  with  an  excess  of  phenol  in  the  absence  of 
a  solvent  to  form  only  the  ortho  and  para  mercurated  phenols.     This 
differs  from  the  action  in  water  which  gives  a  large  amount  of  the  di- 
product  even  in  the  presence  of  a  large  excess  of  phenol. 

2.  The  hydroxyphenylmercuric  chlorides  and  the  corresponding   di- 
mercury  acetate  are  split  by  iodides;  mercuric  iodide,  phenol,  and  a  base 
are  formed.    Bromides  cause  a  partial  splitting,  chlorides  none  at  all. 

3.  The  acetylated  compounds  are  not  split  by  potassium  iodide  in  the 
way  that  the  phenols  are.    They  give  the  organomercuric  iodides  and,  in 
the  case  of  the  ortho  compound,  a  small  amount  of  the  corresponding  mer- 
cury diphenyl  derivative. 

4.  Both  of  the  acetylated  chlorides  react  with  cone,  sodium  thiosulfate 
solution  to  give  the  corresponding  acetylated  mercury  diphenols. 

5.  The  acetylated  mercury  diphenols,  when  treated  with  dil.  sodium 
hydroxide,  not  only  lose  the  acetyl  groups  but  suffer  a  splitting  of  the 
Hg-C  linkage  which  leaves  a  monophenylmercuric  derivative.    This,  ap- 
parently, is  a  new  method  of  breaking  an  Hg-C  bond. 

EVANSTON,  lU,. 


[Reprinted  from  the  Journal  of  the  American  Chemical  Society, 
Vol.  XLV.     No.  7.     July,  1923.] 

[CONTRIBUTION  FROM  THE  CHEMICAL  LABORATORY  OF  THE  COLLEGE  OF  LIBERAL  ARTS  OF 
NORTHWESTERN  UNIVERSITY] 

SOME  MERCURY  DERIVATIVES  OF  PHENOL  ETHERS1 

BY  FRANK  C.  WHITMORE  AND  EDMUND  BURRUS  MiDDLETON2 

Received  February  23,  1923 

In  an  earlier  paper3  it  was  shown  that  mercurated  phenols  react  with 
iodides  of  alkali  metals  to  give  the  original  phenols,  inorganic  mercury 
compounds  and  1  equivalent  of  alkali  for  each  carbon-mercury  linkage 
broken.  When,  however,  the  hydroxyl  group  is  protected  by  acylation 
iodides  react  in  quite  a  different  way  giving  mercuri-bis  compounds  and 
inorganic  mercury  compounds  but  not  alkali.  The  two  processes  may  be 
illustrated  as  follows. 

HO— C6H4— Hgl  +  3  KI  +  H20  >  C6H6OH  +  K2HgI4  +  KOH 

2  AcO— C6H4— Hgl  +  2  KI  — >  (AcO— C6H4)2Hg  -f-  K2HgI4 

The  present  work  was  undertaken  to  determine  the  effect  of  replacing 
the  phenolic  hydrogen  by  an  alkyl  group  instead  of  an  acyl  group.  An 
observation  made  by  Dimroth4  indicated  that  the  effect  of  the  2  groups 
might  be  similar.  In  determining  the  structure  of  0-chloromercuri-phenol, 
he  treated  it  with  ethyl  iodide  in  alkaline  alcoholic  solution  to  prepare  the 
known  o-phenetylmer curie  iodide.  Besides  the  desired  product  he  ob- 
tained a  good  yield  of  0-mercury-diphenetyl.  Since  sodium  iodide  is 
formed  in  the  reaction  it  seemed  reasonable  that  it  might  change  the 
mercurated  phenetole  first  formed  to  the  mercuri-bis  compound.  Dim- 
roth's  results  may  then  be  formulated  as  follows. 

NaO— C6H4— HgCl  +  RI  >  RO— C6H4— HgCl  -f  Nal 

2  RO— C6H4— HgCl  +  4  Nal  — >  (RO— C6H4)2Hg  +  Na2HgI4  +  2  NaCl 

In  order  to  test  this  theory  and  to  study  further  the  effect  of  protecting  a 
phenolic  hydroxyl  group  upon  the  stability  of  the  carbon-mercury  linkage, 
the  action  of  potassium  iodide  on  mercurated  phenol  ethers  was  studied, 
lodomercuri-anisoles  and  -phenetoles  were  prepared  by  the  method  of 
Dimroth.4  As  the  oriho  mercurated  compounds  are  much  more  soluble 
than  the  para  compounds,  the  study  was  limited  to  the  former.  When 
an  alcoholic  solution  of  o-iodomercuri-anisole  or  of  0-iodomercuri-phenetole 
is  refluxed  with  potassium  iodide,  no  splitting  of  the  carbon-mercury  linkage 
takes  place  as  no  alkali  is  formed.  o-Mercury-dianisyl  or  0-mercury- 
diphenetyl  is  obtained  in  good  yield.  The  mother  liquors  contain  large 
amounts  of  inorganic  mercury  compounds.  Potassium  thiocyanate  acts 

1  Presented  at  the  Rochester  Meeting  of  the  American  Chemical  Society,  April, 
1921. 

2  Research  Fellow  under  a  grant  from  the  U.  S.  Interdepartmental  Social  Hygiene 
Board,  General  M.  W.  Ireland,  Chairman.     Some  of  the  organic  mercury  compounds 
related  to  those  studied  are  being  investigated  pharmacologically  under  the  direction  of 
Dr.  A.  S.  Loevenhart  of  the  Department  of  Pharmacology  of  the  University  of  Wisconsin. 

3  THIS  JOURNAL,  43,  622  (1921). 

4  Dimroth,  Ber.,  32,  763  (1899). 


1754  FRANK  C.  WHITMORE  AND  KDMUND  B.  MIDDU3TON  Vol.  45 

like  potassium  iodide  but  gives  poorer  yields  of  the  mercuri-bis  compounds. 

The  para  mercurated  phenol  ethers  react  to  some  extent  with  potassium 
iodide  or  with  potassium  thiocyanate;  some  inorganic  mercury  is  formed. 
No  alkali  is  found.  The  corresponding  mercuri-bis  compounds  are  not 
obtainable  in  a  pure  state  by  these  reactions. 

Sodium  thiosulfate  is  the  most  convenient  reagent  for  making  the 
mercuri-bis  compounds  of  the  phenol  ethers.  The  0 -iodomercuri  com- 
pounds dissolve  readily  in  it  giving  solutions  from  which  the  mercuri-bis 
compounds  separate  on  standing. 

o-Mercury-dianisyl  and  o-mercury-diphenetyl  react  normally  with  mer- 
curic chloride;  quantitative  yields  of  the  chloromercuri  compounds  are 
obtained. 

Experimental  Part 

Preparation  of  o-  and  £-Iodomercuri-phenetoles. — A  mixture  of  5  g.  of  o-chloro- 
rnercuri-phenol3  in  50  cc.  of  50%  ethyl  alcohol,  0.7  g.  of  sodium  hydroxide,  and  3.5  g.  of 
ethyl  iodide  is  heated  gently  for  1  hour.  A  small  amount  of  o-mercury-diphenetyl 
separates  as  the  solution  cools.  This  is  removed  and  the  filtrate  is  diluted  with  water 
to  precipitate  the  o-iodomercuri-phenetole  which  is  recrystallized  from  alcohol;  yield, 
7  g.  The  para  compound  is  prepared  in  a  similar  way.  Five  g.  of  />-chloromercuri- 
phenol  gives  5  g.  of  a  mixture  of  the  corresponding  iodomercuri  and  mercuri-bis-com- 
pounds  which  is  difficult  to  separate.  Because  the  ortho  compounds  are  obtained  more 
easily,  the  experiments  with  potassium  iodide,  with  thiocyanate,  and  with  thiosulfate 
were  carried  out  with  o-iodomercuri-phenetole  and  0-iodomercuri-anisole. 

Preparation  of  o-Iodomercuri-anisole. — Eight  g.  of  o-chloromercuri-phenol,  1  g.  of 
sodium  hydroxide,  50  cc.  of  alcohol,  and  3  g.  of  methyl  iodide  are  heated  for  half  an  hour. 
About  1  g.  of  0-mercury-dianisyl  separates  as  the  solution  cools.  Dilution  of  the  mother 
liquor  with  water  gives  7  g.  of  the  iodomercuri  compound. 

Reaction  of  Potassium  Iodide  with  o-Iodomercuri-anisole  and  with  o-Iodomercuri- 
phenetole. — Four  g.  of  o-iodomercuri-anisole,  recrystallized  from  alcohol,  is  heated 
under  a  reflux  condenser  for  6  hours  with  3  g.  of  potassium  iodide  and  50  cc.  of  alcohol. 
When  the  product  is  cooled  and  diluted  somewhat  the  o-mercury-dianisyl  is  precipitated. 
It  is  recrystallized  from  alcohol;  yield,  1.5  g. ;  m.  p.,  108°.  The  filtrate  from  the  reaction 
mixture  is  neutral  and  gives  an  immediate  precipitate  with  hydrogen  sulfide. 

A  solution  of  2  g.  of  o-iodomercuri-phenetole  in  50  cc.  of  alcohol  together  with  2  g.  of 
potassium  iodide  is  refluxed  for  1  hour.  When  this  product  is  cooled  and  diluted  with 
water,  1.5  g.  of  0-mercury-diphenetyl  separates.  After  crystallization  from  alcohol  it 
melts  at  81  °.  The  filtrate  is  not  alkaline.  It  contains  inorganic  mercury  compounds. 

Reaction  of  Potassium  Thiocyanate  with  the  o-Iodomercuri-phenol  Ethers. — A 
mixture  of  2  g.  of  o-iodomercuri-anisole,  2  g.  of  potassium  thiocyanate  and  50  cc.  of  al- 
cohol was  heated  under  a  reflux  condenser  for  3  hours.  The  product,  cooled  and  diluted, 
gave  1.5  g.  of  the  mercuri-bis  compound.  Recrystallization  from  alcohol  raised  the 
melting  point  only  to  75-80°.  The  filtrate  contains  inorganic  mercury  compounds  but 
is  neutral. 

A  mixture  of  1.6  g.  of  o-iodomercuri-phenetole,  2  g.  of  potassium  iodide  and  50  cc.  of 
alcohol,  heated  under  a  reflux  condenser  for  3  hours  gives  0.8  g.  of  the  mercuri-bis 
compound  melting  at  80°  after  several  crystallizations  from  alcohol. 

Reaction  of  Sodium  Thiosulfate  with  the  o-Iodomercuri-phenol  ethers. — Two  g.  of 
o-iodomercuri-phenetole  dissolved  in  a  solution  of  4  g.  of  sodium  thiosulfate  in  50  cc.  of 
water  deposits  1.2  g.  of  the  mercuri-bis  compound  on  standing;  m.  p.,  81-83°. 


July,  1923     MERCURY  DERIVATIVES  OF  PHENOL  ETHERS       1755 

Similarly,  o-iodomercuri-anisole  gives  the  mercuri-bis  compound  melting  at  108°. 

Reaction  of  the  £-Iodomercuri-phenol  Ethers  with  Potassium  Iodide  and  with 
Potassium  Thiocyanate.— The  reactions  between  these  substances  apparently  lead  to 
the  formation  of  mercuri-bis  compounds,  as  the  filtrates  contain  inorganic  mercury  and 
are  not  alkaline.  However,  the  products  are  very  difficult  to  purify. 

Reaction  of  Mercuric  Chloride  with  the  Mercuri-bis-phenol  Ethers.-MDne  g.  of 
0-mercury-dianisyl  is  heated  with  0.7  g.  of  mercuric  chloride  in  25  cc.  of  alcohol  for  15 
minutes.  The  chloride  deposits  on  cooling,  and  is  recrystallized  from  alcohol;  m.  p., 
177-178°.  Dimroth  obtained  the  same  compound  in  small  amount  by  direct  mercura- 
tion  of  anisole.  He  gives  the  melting  point  as  173-174°. 

Similarly,  o-mercury-diphenetyl  reacts  with  mercuric  chloride  to  give  pure  o-chloro- 
mercuri-phenetole . 

Summary 

1.  Protection  of  the  hydroxyl  groups  in  mercurated  phenols  by  alkyla- 
tion  has  the  same  effect  as  protection  by  acylation,  that  is,  the  stability 
of  the  carbon-mercury  linkage  to   iodides,    thiocyanates,    and    to   thio- 
sulfates  is  increased. 

2.  Mercurated  phenol   ethers  react  with  iodides,   with  thiocyanates, 
and  with  thiosulfates  to  form  the  corresponding  mercuri-bis  compounds 
giving  solutions  which  contain  inorganic  mercury  but  no  alkali,  showing 
that  the  protection  of  the  phenolic  hydroxyl  has  prevented  the  splitting 
of  the  carbon -mercury  linkage  with  the  accompanying  formation  of  alkali 
which  occurs  with  the  mercurated  phenols. 

3.  The  formation  of  the  mercuri-bis  compounds  takes  place  much  more 
readily  in  the  case  of  the  ortho  compounds  than  with  the  para  compounds. 

EVANSTON,  ILLINOIS 


[Reprinted  from  The  Journal  of  the  American  Chemical  Society, 
Vol.  XLV,  No.  5.     May,  1923.] 


[CONTRIBUTION  PROM  THE  CHEMICAL  LABORATORY  OP  THE  COLLEGE  OP  LIBERAL  ARTS 
OF  NORTHWESTERN  UNIVERSITY] 

MERCURY    DERIVATIVES    OF    SALICYLALDEHYDE    AND    THE 
NITRO-SALICYLALDEHYDES1 

BY  FRANK  C.  WHITMORE  AND  EDMUND  BURRUS  MmoLETON2 

Received  February  15,  1923  s 

Aromatic  aldehydes  cannot,  as  a  rule,  be  mercurated  by  mercuric  acetate 
because  of  its  oxidizing  action.  At  the  time  the  present  work  was  done 
the  only  mercurated  aromatic  aldehyde  was  a  mercury  vanillin  of  un- 
determined structure.3  More  recently  the  3  hydroxybenzaldehydes 
have  been  mercurated.1*  Definite  mercuration  products  have  also  been 
obtained  from  vanillin.4  Salicylaldehyde  was  chosen  for  the  present 
study  because  of  its  resistance  to  oxidation  and  because  of  the  activating 
effect  of  the  phenolic  hydroxyl. 

Salicylaldehyde  reacts  readily  with  two  molecular  proportions  of  mer- 
curic acetate  in  alcohol  to  form  3,5-diacetoxymercuri-salicylaldehyde. 
No  oxidation  takes  place,  as  shown  by  the  absence  of  mercurous  acetate 
and  metallic  mercury  from  the  products.  The  dichloromercuri  compound 
is  made  in  the  usual  way  from  an  acetic  acid  solution  of  the  acetate  and 
a  chloride  solution.  Even  when  only  1  molecular  proportion  of  mercuric 
acetate  is  used  the  chief  product  is  the  dimercurated  compound,  although 
a  small  amount  of  a  monomercurated  product  can  be  obtained  from  the 

1  Presented  at  the  Birmingham  Meeting  of  the  American  Chemical  Society,  April, 
1922.     Since  the  presentation  of  this  paper  an  article  has  appeared  by  Henry  and  Sharp 
on  the  mercury  derivatives  of  the  three  hydroxybenzaldehydes.     (a)  /.  Chem.  5oc.,  121, 
1055  (1922). 

2  Research  Fellow  under  a  grant  from  the  U.  S.  Interdepartmental  Social  Hygiene 
Board,  General  M.  W.  Ireland,  Chairman.     Some  of  the  compounds  prepared  are  being 
investigated  pharmacologically  under  the  direction  of  Dr.  A.  S.  Loevenhart  of  the 
Department  of  Pharmacology  of  the  University  of  Wisconsin. 

'  "Realenzyklopaedie  fur  Pharmazie,"  vol.  VII,  p.  100. 
--     4  Paolini,  Gazz.  chim.  ital.,  51,  II,  188  (1921);  C.  A.,  16,  557  (1922) 


May,  1923       MERCURY  DERIVATIVES  OF  SAUCYI,AIJ>£HYD£S  1331 

reaction  mixture.  Since  phenol  can  be  changed  to  monomercurated 
products  by  adding  mercuric  acetate  to  an  excess  of  phenol  without  a 
solvent5  it  seemed  likely  that  salicylaldehyde  might  be  mercurated  in  the 
same  way.  Such,  however,  was  found  not  to  be  the  case.  The  failure  is 
apparently  due  to  the  fact  that  the  mercuration  products  of  salicylaldehyde 
are  insoluble  in  an  excess  of  the  parent  substance,  while  those  of  phenol 
are  soluble  in  the  excess  of  phenol. 

In  order  to  obtain  a  monomercurated  aldehyde  easily,  the  mononitro- 
salicylaldehydes  are  used.  Mercuration  by  mercuric  acetate  in  alcohol 
readily  gives  3-acetoxymercuri-5-nitro-salicylaldehyde  and  5-acetoxy- 
mercuri-3-nitro-salicylaldehyde.  The  corresponding  chloromercuri  com- 
pounds are  prepared  in  the  usual  way. 

The  mercurated  salicylaldehydes  dissolve  in  aqueous  alkali.  The 
alkaline  solutions,  precipitated  by  dil.  hydrochloric  acid,  give  the  chloro- 
mercuri compounds.  The  alkali  salts  in  the  case  of  the  nitro  compounds 
can  be  recrystallized  from  hot  water.  They  are  highly  colored,  indicating 
a  quinoid-acinitro  structure.6 

The  mercurated  salicylaldehydes  condense  with  primary  aromatic 
amines  forming  colored  Schiff's  bases.  Diacetoxymercuri-salicylaldehyde 
has  been  condensed  in  this  way  with  aniline,  ^-toluidine,  ^-aminobenzoic 
acid  and  anthranilic  acid.  The  mercurated  nitro-salicylaldehydes,  both 
acetates  and  chlorides,  have  been  condensed  with  these  amines.  In  the 
case  of  the  acetoxymercuri  compounds,  one  molecule  of  acetic  acid  is  lost. 
Since  this  loss  occurs  only  with  the  nitro  compounds  the  products  are 
probably  anhydrides  or  inner  salts  formed  between  the  acinitro  and  hy- 
droxymercuri  groups.4  Thus  the  product  of  the  condensation  of  3-acetoxy- 
mercuri-5-nitro-salicylaldehyde  with  aniline  would  be  as  follows. 

O 

Hg 


Yl 

=N-0 


O=N- 

The  corresponding  chloromercuri  compound  condenses  with  amines  with- 
out anhydride  formation.  As  would  be  expected  the  products  are  less 
highly  colored  than  the  anhydrides. 

The  mercurated  salicylaldehydes  react  with  hydroxylamine  and  with 
phenylhydrazine,  giving  metallic  mercury.  The  Perkin  reaction  with 
acetic  anhydride  and  sodium  acetate  gives  tarry  products  from  which  no 
pure  substance  has  been  obtained. 

With  potassium  iodide  the  mercurated  salicylaldehydes  behave  like 

6  THIS  JOURNAL,  43,  622  (1921). 

6  Compare  the  work  of  Hantzsch  and  Auld  on  the  mercurated  nitrophenols.     Ber., 
39,  1117  (1906). 


1332  FRANK  C.  WHITMORK  AND  EDMUND  B.  MIDDIvETON  Vol.  45 

the  mercurated  phenols,  losing  mercury  with  the  formation  of  the  un- 
mercurated  aldehydes,  potassium  mercuric  iodide  and  potassium  hydroxide. 
The  instability  of  the  C-Hg  linkage  in  these  compounds  is  due  to  the 
presence  of  the  phenolic  hydroxyl.  When  the  latter  is  protected  by 
acetyl,  methyl  or  ethyl,  the  decomposition  by  iodides  follows  a  different 
course.  The  properties  and  reactions  of  such  derivatives  of  the  mercurated 
salicylaldehydes  are  being  studied  by  one  of  us  (M.). 

Experimental  Part 

3,5-Diacetoxymercuri-salicylaldehyde. — Ten  g.  of  salicylaldehyde  and  52  g.  of 
mercuric  acetate  (2  molecular  proportions)  are  dissolved  in  500  cc.  of  50%  alcohol  con- 
taining 5  cc.  of  acetic  acid.  After  the  mixture  has  been  heated  for  1  hour  on  the  steam- 
bath  it  is  cooled  and  filtered.  The  crude  diacetate  obtained  weighs  32  g.  On  standing 
overnight  10  g.  more  separates.  Addition  of  sodium  chloride  solution  to  the  filtrate 
precipitates  8  g.  of  crude  dichloromercuri-salicylaldehyde.  The  diacetate  is  insoluble 
in  all  ordinary  organic  solvents  except  glacial  acetic  acid  in  which  it  is  soluble  in  the  pro- 
portions of  about  1 :  5  in  the  boiling  solution  and  1 : 10  in  the  cold.  It  separates  in  needles 
which  melt  with  decomposition  at  234°  (uncorr.).  The  crude  material  melts  with  de- 
composition at  about  225 °.7  It  is  soluble  in  aqueous  sodium  hydroxide.  Boiling  with 
alcoholic  potassium  iodide  removes  all  the  mercury  as  potassium  mercuric  iodide  forming 
salicylaldehyde  and  potassium  hydroxide.  The  diacetate  reacts  with  hydroxylamine 
and  with  phenylhydrazine  as  an  oxidizing  agent,  forming  metallic  mercury. 

Analyses.*    Calc.  for  CiiH10O6Hg2:  Hg,  62.8.     Found:  Hg,  6.24,  62.8. 
The  dichloromercuri  compound  is  insoluble  in  organic  solvents  and  does  not  melt  at  270°. 

Analysis.     Calc.  for  C7H4O2Cl2Hg2 :  Hg,  67.7.     Found:  67:8. 

3(?)-Chloromercuri-salicylaldehyde. — Attempts  to  make  this  substance  by  mer- 
curation  of  an  excess  of  salicylaldehyde  without  a  solvent  failed,  apparently  because  of  the 
insolubility  of  the  mercurated  products  in  the  salicylaldehyde.  Ten  g.  of  salicylaldehyde 
in  2  liters  of  water  is  treated  with  26  g.  of  mercuric  acetate  (1  molecular  proportion) 
and  the  mixture  is  stirred  mechanically.  As  soon  as  the  solution  no  longer  gives  a  test 
for  inorganic  mercury  with  sodium  hydroxide  it  is  filtered.  Three  g.  of  the  diacetate 
is  thus  obtained.  Addition  of  sodium  chloride  solution  to  the  filtrate  gives  19  g.  of  a  mix- 
ture of  mono-  and  dichloromercuri  compounds.  Repeated  extractions  with  boiling  alco- 
hol remove  5  g.  of  a  pure  monochloromercuri-salicylaldehyde;  m.  p.,  189-190°.  Sus- 
pended in  chloroform  and  treated  with  1  molecular  proportion  of  iodine  it  gives  an 
iodo-salicylaldehyde;  m.  p.,  52-58°.  This  is  apparently  the  3-iodo-salicylaldehyde 
which  is  reported  to  melt  at  55°.  The  residue  insoluble  in  hot  alcohol  appeared  by  anal- 
ysis to  be  a  mixture  of  dichloromercuri-  and  monochloromercuri-salicylaldehydes. 
The  latter  is  probably  the  5-chloromercuri  compound.  No  method  of  separating  this 
mixture  has  been  found. 

Analysis.     Calc.  for  Cr^O^ClHg:  Hg,  56.3.     Found:  56.4. 

Nitration  of  Salicylaldehyde.9 — 3-Nitro-  and  5-nitro-salicylaldehydes  were  pre- 
pared according  to  the  method  described  by  Miller. 

3-Acetoxymercuri-5-nitro-salicylaldehyde. — Twelve  g.  of  5-mtro-salicylaldehyde 
and  23  g.  of  mercuric  acetate  dissolved  in  400  cc.  of  alcohol  containing  5  cc.  of  acetic  acid 
are  heated  1  hour  on  the  steam-bath.  The  precipitate  is  filtered,  washed  and  dried; 

7  Henry  and  Sharp  give  the  melting  point  as  133°. 

8  For  method  of  analysis  see  note,  THIS  JOURNAL,  44,  1548  (1922). 

9  Miller,  Ber.,  20,  1928  (1887). 


May,  1923       MERCURY  DERIVATIVES  OF  SAUCYLAU>EHYDES  1333 

yield,  26  g.  It  is  crystallized  from  glacial  acetic  acid,  the  only  organic  solvent  in  which  it 
is  appreciably  soluble.'  It  forms  pale  yellow  crystals  which  do  not  melt  at  260°.  It 
dissolves  in  aqueous  sodium  hydroxide  to  give  a  yellow  solution. 

Analyses.     Calc.  for  C9H7O6NHg:  Hg,  47.1.     Found:  47.1,  47.1. 

5-Acetoxymercuri-3-nitro-salicylaldehyde. — Four  g.  of  3-nitro-salicylaldehyde  and 
7  g.  of  mercuric  acetate  are  treated  as  described  above.  The  product  weighs  9  g. 
It  is  recrystallized  from  glacial  acetic  acid.  It  does  not  melt  at  260°. 

Analysis.     Calc.  for  C9H7O6NHg:  Hg,  47.1.     Found:  46.9. 

3-Chloromercuri-5-nitro-salicylaldehyde. — Ten  g.  of  the  corresponding  acetate 
dissolved  in  dil.  sodium  hydroxide  solution  and  acidified  with  dil.  hydrochloric  acid  pre- 
cipitates 8  g.  of  the  chloride.  The  substance  is  insoluble  in  organic  solvents  and  does 
not  melt  at  260°. 

Analyses.     Calc.  for  C7H4O4NClHg:  Hg,  49.9.     Found:  49.1,  49.3. 

Condensation  of  Mercurated  Salicylaldehydes  with  Aromatic  Amines 

Schiff's  bases  are  obtained  by  heating  the  mercurated  salicylaldehydes  with  an  ex- 
cess of  aniline  or  />-toluidine.  Similar  compounds  are  obtained  from  the  aminobenzoic 
acids  by  refluxing  the  latter  in  alcohol.  Less  pure  products  can  be  obtained  by  refluxing 
the  aldehydes  with  the  aminobenzoic  acids  in  acetic  acid. 

3,5-Diacetoxymercuri-salicylal-aniline. — Five  g.  of  the  mercurated  aldehyde  dis- 
solved in  10  cc.  of  hot  aniline  and  cooled  gives  5.5  g.  of  a  brick-red  amorphous  product 
which  is  insoluble  in  organic  solvents  and  does  not  melt  at  260°.  The  crude  product  is 
washed  thoroughly  with  benzene  and  dried  at  100°  for  analysis. 

Analyses.     Calc.  for  Ci7Hi5O6NHg2 :  Hg,  56.2.     Found:  56.2,  56.8. 

3,5-Diacetoxymercuri-salicylal-p-toluidine. — The  preparation  and  properties  of 
this  substance  are  similar  to  those  of  the  aniline  compound. 

Analyses.     Calc.  for  Ci8H17O6NHg:  Hg,  55.1.     Found:  54.6,  54.9. 

3,5-Diacetoxymercuri-sah'cylal-^-ammobenzoic  Acid. — Five  g.  of  the  aldehyde 
yields  5.5  g.  of  a  deep  red,  insoluble  powder  which  does  not  melt  at  250°. 

Analysis.     Calc.  for  C18H15O7NHg2 :  Hg,  52.9.     Found:  53.0. 

The  substance  is  soluble  in  dil.  alkali.  Precipitation  by  acetic  acid  gives  a  product 
richer  in  mercury  (56.7% ) .  This  may  consist  of  anhydride  or  a  partly  hydrolyzed  product 
in  which  one  of  the  acetoxymercuri  groups  has  been  changed  to  an  hydroxymercuri  group.10 

3,5-Diacetoxymercuri-salicylal-anthranilic  Acid. — The  preparation  and  properties 
of  this  substance  are  similar  to  those  of  the  ^-aminobenzoic  acid  compound. 

Analysis.     Calc.  for  C]8Hi5O7NHg2:  Hg,  52.9.     Found:  52.3. 

3(?)-Chloromercuri-salicylal-aniline. — Two  g.  of  the  alcohol-soluble  monochloro- 
mercuri-salicylaldehyde  dissolved  in  4  g.  of  hot  aniline  gives  on  cooling  2  g.  of  flat,  yellow 
plates  which  are  insoluble  in  organic  solvents;  m.  p.,  182-184°. 

Analysis.     Calc.  for  Ci3Hi0ONClHg :  Hg,  46.4.     Found:  46.5. 

Anhydride  of  3-Hydroxymercuri-5-nitrosalicylal-aniline. — Five  g.  of  3-acetoxy- 
mercuri-5-nitro-salicylaldehyde  dissolved  in  8  cc.  of  hot  aniline  and  cooled  gives  a  deep 
red  amorphous  product  which  is  insoluble  in  organic  solvents  but  is  soluble  in  alkali. 
It  does  not  melt  at  250°.  Analyses  show  that  1  molecule  of  acetic  acid  has  been  lost 
during  the  condensation  or  during  the  drying  of  the  product.  This  probably  takes  place 
between  the  acinitro  and  acetoxymercuri  groups.6 

Analyses.     Calc.  for  Ci3H8O3N2Hg:  Hg,  45.5;  C,  35.4.     Found:  Hg,  45.6;  C,  35.0. 

1°  White,  THIS  JOURNAL,  42,  2363  (1920). 


1334  FRANK  C.  WHITMORE  AND  EDMUND  B.  MIDDLETON  Vol.  45 

A  similar  product  is  formed  from  aniline  and  5-acetoxymercuri-3-nitro-salicylalde- 
hyde. 

3-Chloromercuri-5-nitrosalicylal-anilme. — Three  g.  of  the  aldehyde  dissolved 
in  8  cc.  of  hot  aniline  and  cooled  gives  an  orange-red  product  which  is  insoluble  and  does 
not  melt. 

Analyses.     Calc.  for  Ci3H9O3N2ClHg:  Hg,  42.1.     Found:  42.5,  42.8. 

Summary 

1.  Mercuration  of  salicylaldehyde  by  mercuric  acetate  gives  mainly 
a  dimercurated  product  with  only  small  amounts  of  a  monomercurated 
aldehyde. 

2.  The  two  nitro-salicylaldehydes  give  normal  mercuration  products. 

3.  The  mercurated  salicylaldehydes  lose  all  their  mercury  when  treated 
with  potassium  iodide,  hydroxylamine  or  phenylhydrazine. 

4.  The  mercurated  salicylaldehydes  form  Schiff  s  bases  with  aromatic 
amines. 

EVANSTON,  ILLINOIS 


Gaylord  Bros. 

Makers 
Stockton,  Calif. 

PAT.  JAN.  21,  1908 


60SG03 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 


